Help! O2 sensor!
 

Do The Truck O2 Sensors Interchange 5.3 Front/6.0 Rear?
I have an '01 5.3 in my 1950 chevy truck and I bought a set of GM rear o2 sensors that look the same but have a different connector. I can change the plug, but will they work correctly? The ls1 guys interchange front/rear with no problem.
B.T.W. the part number I have is 25333817.

My front and rears are identical. Same connectors as well.

Looks like some 01s came with Delphi and some with Denso sensors. With the Delphis the front and rear have different connectors(rear are square). Wire colors match up correctly though. With the Densos both front and rear have the square connectors. I have the Densos.

Attachment 138384

The ones that came with the motor are Denso #12562943 (black, black, blue, white) with a square female connector. The replacements that I have are Delphi #125333513 (brown, brown, tan, purple) and have a square male connector.

What did the motor come out of?

2001 chevy silverado

Are the wire colors on the harness the same? Is the harness from the same vehicle? All of the 01s I looked up in my service manual use the colors shown above irrespective of the sensor manufacturer. Other than the 6.0L which is shown below.

Attachment 138385

Ya, the wires in my harness are pink, black, purple/white, and tan/white as in the 2001 5.3L diagram. The denso sensor that was plugged into it was blk, blk, blue, white.
It was the original correct OEM sensor part # that was in there.
I want to replace it with a new pair of o2 sensors that I have lying around.

Basically, I want to replace the Denso #12562943 with the Delphi #125333817
I want to replace my old front o2 sensors with some newer model rear 6.0l rear sensors
all I have to do is swap the connectors and they will plug in.
DrX, by chance do you have a pinout diagram like the above ones that contain the 12562943 and 125333817 sensors? That would also be helpful.

I don't have schematics for the sensors themselves. Looks like part #25333817(AC Delco 2131149) is a rear sensor from an 02 6.0L. 02s used either case grounded or isolated grounded sensors. Not sure which this is as all of the rear connectors are the same. Circuitry varies with sensor type and they may not be interchangeable.

But, if you have Tan/W wires on your bank 1 sensors(2001), you require case-grounded sensors. The front and rear connectors will also be different as you have described. Now, for the 01s it looks like the Delphis are the case-grounded as they are used in the circuits with Tan/W wires. But then why did you have Densos in there?? 02 schematics for the connectors use case-grounded/isolated-rounded vs Denso/Delphi in the 01 schematics. Gets a little confusing doesn't it? From the schematics it looks like pin A will be grounded to the sensor case if it is case-grounded. So you could try testing for continuity between pin A and the case to determine which sensor types you have. Hope that works.

sorry for bumping an old thread

but are the front o2 sensors from an 2005 the same as those in 2001 ?